Good day, everyone!
At the request of AKAKEN, I have composed a list of the Noticeable and Prestigious Victories that made it into the game! I will start at the top row and move from left to right.
Noticeable Victories:
Note: Although there are 42 entries in Prestigious Victories, there are only 35 entries in this one, with the entire far-right row and the top-right space empty. So that mysterious empty spot to the right of Yen Karis and above Mazurine truly is empty, unfortunately!
1. Markus Genbel - Assassin's Den (missable, must get before completing Mosquito Swamp quest!)
2. Kil-Ka-S'hor - Crypt of 7000 Skulls
3. Soul Torturer - Crypt of 7000 Skulls
4. Varakular - Unmissable, the first boss
5. Yen Karis - Metrolia Castle: Throne Room (missable, must get before completing Mosquito Swamp quest! Talk to the guard to the right of the Royal Family after defeating Varakular and first leaving Metrolia.)
6. Evil Drake - His Lair (South of the Woods of Lupantha, extreme southern end of the map)
7. Ice Dragon - His Lair (Lannion Lands)
8. Razor Mouth - His Lair (North of Woods of Lupantha, west of Gargael Mountains entrance)
9. Skull Collector - Mosquito Swamp (Keep going left!)
10. Felicia - Metal Guard
11. Mazurine - Mosquito Swamp
12. Zurabor (Catarsis Demon) - His Home - West of Metrolia (Talk to the weird mushroom creature at the counter far-west of Metrolia to unlock this house on the map)
13. Sour Angels - Shrine of Yveen (Yveen's Brotherhood quest)
14. Dogmahr - Gargael Mountains
15. Beastie - Metal Guard
16. Panga Cupidon - Unmissable, story boss in Mosquito Swamp
17. Evalyn Almighty - Secret Elven Community
18. Alisia Cancellara - Lord Zarmon's Crypt
19. Argodus - Armanis Coast
20. Lord Rusham - Unmissable, story boss in Crystal Palace
21. Terror Boar - Tongo-Boga (Fighter's Guild rank quest)
22. Karl Ludenborg - His home (south Lupantha Woods)
23. Lanfest - Coliseum, final opponent in the Solo Tournament
24. Wolf - Lower Mountain Range (Unmissable, story event)
25. Two-Headed Machine - Pirates' Coast - North side
26. Sainberle - Unmissable, story boss in Giants' Fortress
27. Moat Legend - Giant's Fortress Sewers (I guess it's technically missable, if you went out of your way to avoid it, but that would be fairly difficult!)
28. Hellbound Heart - Unmissable, story boss in Lucida Tower
29. Eastern Teszrandus - Elven Glade, just west of Metrolia (accessible on Day 13 with Sarah and Nash; to activate this fight and complete the quest, get Sarah inflicted with Venom by fighting that Venom Lycose that appears in your HQ also on Day 13)
30. The Machine - House of Pain (missable, must bring Daghmar from the Guild of the Dragon to the House of Pain's doors with Coryool BEFORE escorting him to the inn in Metrolia!)
31. Zoo - Unmissable, story boss
32. Vanczik (Hell Murderer) - Abandoned Forge in Lannion Lands
33. Ordhan the Grey - Ordhan's Hideout (Bellenue's Seals quest, available after defeating Rixian)
34. "Iron Arms" Zander - Metal Guard
35. Eastern Teszrandus - Kuko's Marsh, quest to get into the Secret Elven Community
Prestigious Victories:
1. The Underking - Unmissable, story boss
2. Palacia's Legendary Trial - Palacia (Zoo's Level 8 Slayer reward - northeast of Baluul)
3. Lord of the Roots - Gods' Smithy in Metrolia (Unknown Guild's final rank quest)
4. Ratarazzi - Unmissable, story boss at Cape Spine
5. Kranko - Western Metrolian Wastelands (guarding the Treasure House)
6. Jurgandia - Unmissable, story boss at the Castle of Silence
7. Maango Cat - Lannion Lands - quest from the Mayor of Baluul. Just keep running around in the snow and you should encounter it eventually. If not, reset after a few encounters and try again)
8. Lokkas - Centaur Fortress
9. XR-Giga 999 - Unmissable, story boss in Metrolian Airport
10. Slime King - Slime Nest
11. Xayulda the Earth Demon - Lupantha Woods (after defeating the Morph Demon)
12. Mutated Flower - Old Lab of the Dark Order
13. Doom Balrog - Old Lab of the Dark Order
14. Garsp - Unmissable, story boss in Giants' Fortress
15., 16., and 17. Magdalena, Ozur, and Drachknor -Unmissable, story bosses in the Hall of Madness
18. Baron Inferneodon - Unmissable, story boss
19. Zagyodon - Feared Kjeldar Castle
20. Terror of the Seas - His lair (on the island with Gonda Tower)
21. Aglae Dracosphere - His lair (near Aglae-Terra)
22. Evander Holywark - Unmissable, story boss in Angel Town
23. and 24. King Duan and Queen Dyan - Unmissable, story boss in Angel Town
25. Jerva Del Slay - Unmissable, story boss in Assassins' Castle
26. Wasp B2R - Modern Sciences Institute, after defeating Rixian
27. Gigatron RK-0 - same as the wasp
28. Evom Foru - Ore Lab, Guild of the Unknown's training quest
29. Arazom D'Avaren - His glade, north of Yveen's Shrine
30. Nankcho-Nahnga - Dark Order Shrine
31. Queen of Luban-Erya - Pit of Fire
32. Guru-Handa the Inferno God - Pit of Fire
33. Living Horror - Unmissable, story boss in Giants' Fortress
34. Anxu Durahj - Unmissable, story boss in Giants' Fortress
35. Munola D'Albeyn - Unmissable, story boss in Bazizka Tower
36. Bethambuu - Anderson Guard (Van Helsing's quest)
37., 38., 39., 40. and 41. - Dagayel'rr, Evander, Eliza, Orghandi, and Rixian - Unmissable, story bosses
42. Morph Demon - Old Metrolian Castle (True final boss)
There you have it, folks! As always, feel free to ask me anything about the game, and I'll do my best to help. Have a good one!